Bowling pin spotting mechanism



Feb. 12, 1963 T. FLINT ETAL 3,077,348

BOWLING PIN SPOTTING MECHANISM Original Filed Nov. 12, 1948 9 Sheets-Sheet 1 ATTORNEY Feb. 12, 1963 T. FLINT ETAL BOWLING PIN sPoTTING MECHANISM 9 Sheets-Sheet 2 Original Filed Nov. 12, 1948 INVENTORS THOMAS FLmT .Joe-m u. FLUKE Feb. 12, 1963 T. FLINT ETAL 3,077,348

BOWLING PIN SPOTTING MECHANISM Original Filed Nov. 12, 1948 9 Sheets-Sheet 3 FIGIS SW I 3 INVENTORS THOMAS FLINT JOHN M. FLUKE Y ATTORN Y Feb. 12 1963 T. FLINT ETAL BOWLING PIN sPoTTING MECHANISM 9 Sheets-Sheet 4 Original Filed NOV. l2, 1948 mmv INVENTOR S THOMAS FLINT www www SEK d .wmv WWW www JOHN M. FLUKE ATTORNEY wwf Feb. l2, 1963 T. PLANT ETAL. 3,077,348

BOWLING PIN SPQTTING MECHANISM Original Filed Nov. 12, 1948 9 Sheets-Sheet 5 FIG.5

sw13 (sw 1) INVENTORS THOMAS FLINT JOHN M. FLUKE ATTORNEY Feb. 12, 1963 T. FLINT ETAL 3,077,348

BOWLING PIN SPOTTING MECHANISM Original Filed Nov. 12, 1948 9 Sheets-Sheet 6 Fles l ,P 454 lf F l/ fIZ 47s 476 48d 476 482 472 :"/5 6"@ 472 Q l l g 460 N \l\ 482 I 460 lll-11.' E i lll/: I 2 ql l l In I 462 L ail/l l', 11'* 462 457 46a 477 J 4 468 9 -r 469 lo \i452 452%/ 6 46 470 y il? 470 465" 467 46 7", 465 43a R 438 l u n *i452 t?" 454 454 INVENTORSr moms Fun? .norm n. FLUKE ATTORNEY Feb. 12, 1963 T. FLlNT ETAL BOWLING PIN SFOTTING MECHANISM Original Filed Nov. l2, 1948 F I G. 7

9 Sheets-Sheec 7 flo" INVENTOR THOMAS FLIN'T BY JOHN M. FLUKE ATTORNEY Feb. 12, 1963 T. FLINT ETAL 3,077,348

BOWLING PIN SPOTTING MECHANISM Original Filed Nov. 12, 1948 9 Sheets-Sheet 8 f f Q INVENTOR 24 THOMAS FLINT Feb. 12, 1963 1'. FLlNT ETAL. 3,077,348

BOWLING PIN sPoTTING MECHANISM original Filed' Nov. 12, 1948 9 sheets-sheet 9 INVENTOR THOMAS FLINT BY JQHN M. FLUKE ATTORNEY 3,977,348 EWE/LING PIN SPUTHNG MECHANISM Thomas Flint, Concord, Mass., and .lohn M. Finire, Seattle, Wash., assignors to American Machine d: Fonndry Company, a corporation of New Jersey Application May 3, i954, Ser. No. 427,166, now Patent No. 2,977,121, dated Mar. 28, 1961, which is a division ot application Ser. No. 59,706, Nov. 12, i948, now Patent No. 2,736,554, dated Ech. 28, 1956. Divided and this application Feb. i9, i960, Ser. No. 15,010

7 Claims. (Cl. 273-43) This invention relates to bowling pin spotting machines and more particularly to improvements in mechanisrn forming a part thereof for spotting a set of bowling pms in a predetermined playing arrangement or formation on the playing bed of a bowling alley.

This invention relates generally to automatic bowling pin spotting machines, such for example as the types shown in Rundell Patents 2,388,707 and 2,388,709 issued November 13, 1945 in which bowling pins fall or are delivered into the pit of a bowling alley, and are lifted therefrom and conveyed to mechanisms which distribute the pins and transfer them into devices which at the proper time spot them in playing positions on the bed of a bowling alley. While reference is made to machines such as shown in the above referred to Rundell patents, it is to be understood that the structure of the present invention is not limited to this type of machine, but can be readily adapted or use in other types of automatic bowling pin spotting machines if desired.

This application constitutes a division of our co-pending application Ser. No. 427,166, tiled May 3, 1954, now Patent No. 2,977,121, which is a division of our application Ser. No. 59,706, now Patent 2,736,554.

The invention also provides spotting mechanism assembled on a table adapted to be moved vertically to and from a pin receiving position adjacent the distributing mechanism, and the pin spotting position relative to a bowling alley. The spotting mechanism is so arranged on the table that it operates from one side thereof and thereby co-operatively with an electro-mechanical latching mechanism makes it possible to use a simple vertical up and down movement in order to effect the required operation of spotting bowling pins on the pin supporting bed of a bowling alley.

The invention further consists in the provision of pin spotting echanism which is constructed to cause the butt ends of bowling pins to project slightly below the bottom of the table when the table nears the playing bed of the bowling alley during the spotting period. The distance a pin projects may vary in accordance with variations in pin diameters and lengths of pins due to the fact that all pins are supported by partly open doors within which the pins are supported and guided and come to rest thereon in accordance with their diameters for proper delivery to the bowling alley. This construction allows the machine to handle a wide range of pin sizes, which may vary length- Wise and transversely. ln this manner the machine is equally effective in spotting rst quality or league bowling pins, or worn pins, such as generally used in open play, which may have been turned down and shortened or repaired in order to prolong their life.

The invention further consists in the provision of a bowling pin spotting and respotting table which is so designed that it can be located very close to the alley bed 6 in order that pins to be spotted are held under positive control of the spotting members until they practically touch the table. In this way applicants insure maximum accuracy in spotting with a minimum of noise, as compared with prior bowling pin spotting machines in which pins are dropped a considerable distance after their release from their supporting means in the spotting table.

Patented Feh. l2, i963 According to applicants construction, the release of pins to be spotted and respotted is eilected easily and relatively slowly because of the provision of a driving crank arm which swings crosswise as the table is lowered towards the alley imparting substantially a simple harmonic motion to the table, thus reducing the lowering speed of the vertical travel of the table and insuring that pins to be spotted or respotted will be placed gently upon the alley.

It is a further object of the invention to provide an improved pin spotting mechanism having novel means for supporting pins to be spotted and for guiding them into accurate spotting arrangement on the playing bed of a bowling alley.

With these and other obiects not specifically mentioned in View, the invention consists of certain combinations and constructions which will be hereinafter fully described, and then set forth in the claims hereunto appended.

In the accompanying drawings which form a part of this Specilication, and in which like characters of reference indicate the same or like parts:

FiGURE l is a side elevation of the bowling pin setting machine showing the pin distributor in conjunction with the pin spotter and respotter table,

FIGURE 2 is a plan view of the pin spotting-respotting table,

FIGURE 3 is a plan view of a single cell or spottingrespotting unit.

FGURE 4 is an isometric bottom View of the table illustrating the respotting or pin gripper mechanisms during `pin gripping action,

FIGURE 5 is a side elevation, partly in section, of a single spotting-respotting unit of the table,

FIGURE 6 is a sectional end elevation of the same, taken on line 6-6 of FIGURE 5,

FIGURE 7 is a detailed side elevation of the pin gripper control mechanism,

FIGURE 7A is a sectional plan view on line 7A--7A of FIGURE 7,

FIGURE 8 is a detailed side elevation of the pin spotting mechanism for placing new sets of pins on the alley,

FIGURE 9 is an enlarged detailed side elevation of the cam control mechanism for the same.

FIGURE 10 is a partial end elevation of the pin gripper linkage construction, and

FIGURE ll is a detailed sectional end elevation of a Isingle unit of pin grippers taken on line Sli-11 of FIGURE 5.

The present invention is directed to the pin spotting mechanism so that, for other details of the bowling pin spotting machine not disclosed herein, reference is to be had to the aforementioned Patent 2,736,554.

Referring to FIGURE 1, there is shown an endless driven conveyor 5G which delivers bowling pins butt-end first and in succession to a distributor D having a plurality of cups C arranged to deliver the bowling pins to the funnels F of a spotting-respotting table T. The number of cups C and of tunnels F corresponds to the number of pins in play which, in the illustrated embodiment, is ten.

Pin Spotting and Respottng Mechanism Referring to FIGURE l, it will be seen that the pin supporting devices F, into which pins are delivered from distributor D, are mounted on and from a part of pin spotting and respotting table T located beneath distributor D. Table Tis mounted for movement upwardly and downwardly between a pin receiving position beneath distributor D, and pin spotting, and respotting positions relative to alley A. Table T is supported by the opposite side frame members 103 of the machine which are attached to kickbacks K. Table T hangs from a main cross shaft 314 journaled in suitable bearings 3io secured to the top of side frame N3.

`member 3,07?, ses

The `mechanism for supporting and moving table T to and from the pin supporting portion or bed of alley A, is clearly shown in FIGURES l, 7 and 8. Suitably mounted on one side of frame member ltl is a motor N2 which is operated at the proper time during the operation of the machine by controls described hereinafter which effect the up and down motion of table T in order to spot and respot pins on alley A. The shaft of motor M2 is connected, as by means of a liexible coupling Siti, to a suitable gear reduction unit 32d provided with an output shaft 322 on which is keyed sprocket 324. A chain 326 engaging sprocket 324; also engages a larger sprocket 32S keyed to main cross shaft Sie on the opposite ends of which are secured aligned crank arms 330. ln this manner and by means of suitable speed reducing ratios, the desired number of revolutions per minute of shaft Sie is obtained during the periods when motor M2 is energized.

As shown in FIGURE 2, for example, table T preferably is in the form of a generally triangular framework which supports the spotting and respotting devices, and operating mechanisms therefor. Attached to opposite rear corners of table T are upwardly extending members 332 forming a support for a vertical guide plate 334i. Plates 334 engage vertically spaced sets of guide rollers 335 mounted in stationary brackets 333 secured to side frames idf, whereby table T is guided in a substantially vertical path at all times during its upward and downward movement relative to alley A.

A transverse shaft 34d is mounted in bearings 342 mounted on sid-e member 43d of frame structure of table T. At its extremities, shaft 34d supports crank arms 344 mounted for free rotation thereon. Connecting rods or links designated generally 346 connect the free ends of crank arms 336 and 344. As shown in FTGURES l, 7 and 8, each link consists of an intermediate rod section 352, an adjustable threaded sleeve 35%, a connecting 351, and a shock absorber 352i. Sleeve 35i), thro-ugh which a reduced portion of rod section 352 projects, is threadably connected to a bushing 353 threadably secured to shock absorber housing 357. Member 35i is pivotally connected to crank arm 344, and also threadabiy secured to a threaded plug 35S secured in the lower end of housing 357 of shock absorber 354. Enclosed within housing 357 and encircling the reduced portion of rod section 352, are alternating laminations of washers 356, such as steel or other suitable metal or material, and resilient elements 35d, preferably rubber, or other suitable material, which are compressed as a unit by a collar 369 attached to the end of the reduced portion of section 352 in order to cushion shocks and loads imposed upon crank arms 33@ and 344, and for the purpose of imparting a smoother upward -motion to the table during its movement to and from the pin supporting bed of a bowling alley.

The foregoing structure is such that when an excessive load is placed on the table raising and lowering mechanism, as when upward movement of table T is initiated, collar 3&0 compresses the unit comprising washers 356 and resilient elements 358 to a greater extent than under normal operating conditions, and thereby momentarily lengthens rod 346; so also when table T is lowered after the first ball of a frame is rolled.

The upward and downward movement of table T relative to alley A is effected by the movement of crank arms 330 and connecting rods 346. As crank arms 33) travel in a clockwise direction, as viewed in FIGURE l, and the pivotal connections between arms 33t? and rods 346 move past dead center, crank arms 344i move in a counter clockwise direction. ln this manner, table T, which is guided vertically by tracks 33d and rollers 336, is given a substantially straight-line movement to and from alley A. In order to reduce the power required for moving table T upwardly relative to the pin supporting bed of alley A, table T is counterbalanced by weights or a single weight W. As shown in FGURE l, the counterweight is located at the front of the machine, although if desired, it could be located at any other suitable place. Weight W is mounted on the ends of spaced chains 36d which extend upwardly from the weight over spaced sprockets 366 secured to opposite ends of a shaft 363 journaled in suitable bearings in forwardly and upwardly inclined space brackets 37d mounted on the fram-e structure of the machine. Chains 364 pass thence rearwardly over sprockets loosely mounted at the opposite ends of shaft 33t/t and extend downwardly to suitable attaching elements which secure chains 36d to opposite sides of table T at 374. The weight of the table preferably is slightly in excess of counterweight W, so that table T aiways attempts to move downwardly against the action of weight W.

The normal at rest position of table T is designated position ddii, see FlGURE l. In a typical bowling cycle where two balls are employed for each frame, after the rst ball has been rolled, table T moves from position 4&6) upwardly to position 402, thence downwardly to position tid which is termed the respotting position, where standing pins are detected and gripped for lifting and respotting in on or off-spot positions as required by the individual pin positions. Table T then moves upwardly carrying any gripped pins to be respotted to position ldd while a suitable sweep (not shown) operates, removes fallen pins from the alley and deposits them in the alley pit before table T, moving continuously, moves to respotting position 4M, where pins previously picked up, are deposited in their respective previous on or ofi`-spot positions on the alley and released by grippers 454. Table T then moves upwardly to position titi where it remains at rest while the second ball of the same frame is rolled. The second ball having been rolled, the operation of the machine is started and table T moves upwardly to position 492, thence downwardly to position 494 where the presence or absence of any pins remaining standing is detected. However, in this case, any standing pins are not picked up. The table then moves upwardly while the sweep again traverses the pin supporting bed of the alley and removes therefrom all fallen and standing pins. Table T, moving to position 02, receives a set of pins carried by the distributor cups so that when table T descends to its lowest or spotting position ddd, see FIGURE l, a new set of pins, carried by the table in tunnels F, is released and deposited in proper on-spot triangular arrangement on the bed of the alley awaiting rolling of the next ball. Table T continues to move until it arrives at position Atti@ where it comes to rest.

A guard (not shown) may be provided to prevent damage to the table or parts thereof by an inadvertently or carelessly rolled ball during spotting and respotting operations, and also during the operation of the sweep. The guard is raised above the alley to inoperative position relative to alley A whenever the alley is ready for bowling.

lf all pins are knocked down or a strike occurs when the first ball of a frame is rolled, table T moves as before, first up to position db2 and then down to pin detecting? and respotting position 4M and returns as hereinabove explained. The sweep passes rearwardly over the pin supporting bed of the alley, removing thereform all fallen pins, and returns to inoperative position. Table T continues to move upwardly and at pin receiving position 492. a new set of pins in distributor D is discharged into the pin spotting devices or funnels E, after which table T moves all the way down to pin spotting position 4% and spots a new set of pins on the alley. intelligence for accomplishing this is received by the electrical control system owing to the fact that the table has not detected the presence of any standing pins at position 4de.

It will be seen that some of the intervening movements of the table, previously described, which occur in the absence of a strike on the first ball, and some of the movements in the second cycle of operations of table T are eliminated following a, strike play.

Counter-weight chains 354 will obviously have the same reciprocating travel as that of table T in a vertical direction. Chains 3&54 in passing over sprockets 366 cause the rotation of shaft 35S which is directly synchronized with the vertical movement of table T. For the purpose of t indicating the presence or absence of pins after each bail is rolled, for gripping any standing pins for lifting and respotting after the first ball of a frame is rolled and for respotting such pins in their respective on or off-spot positions, it is necessary that the table be maintained in position titr for a period sufficient to carry out these desired operations. A preferred mechanism for accomplishing this result consists of a latch (not shown) attached to one of the sprockets 366. As indicated, the latch is so positioned, that when table T is located at detecting-respotting position 464:, it engages with the plunger of a shock absorber 384i pivotally mounted on the forward portion of main frame 103. The armature of a solenoid S5, which is mounted on bracket 392, is operatively connected to pivot shock absorber 384 in response to energization of solenoid S5, the energization of the solenoid being effective to move the plungers of the shock absorber out of engagement with the latch to permit further downward. movement of table T from position 4M.

Spotter and Respotter Table The frame of table T consists of an upper frame and a lower frame interconnected therewith to form a single unit. The upper frame assembly is essentially triangular in shape and is formed of channel section side members 13G connected at their front ends as viewed at the bottom of FIGURE 2, by a transverse member 432. At their rear ends, channel section side members 430, see FIG- URE 2, are connected by a transverse member 434, which, in the illustrated embodiment, is a rectangular tubular section.

The lower frame assembly consists of longitudinally spaced transverse channel sections 43o, 43S, 445i, 442 and 444, connected by laterally spaced longitudinal channels 445 to form an assembly which makes up a series of ten substantially rectangular cells R, see FIGURE 4. Each cell R has its central vertical axis disposed in substantially vertical alignment with the axis of one of a set of ten pins P supported in spotter tunnels F, the latter being arranged in a pattern corresponding to the playing positions the pins occupy on the alley.

The pin spotting or upper portion of the table includes ten triangularly arranged pin spotting devices designated generally 415i. Each of these devices includes a pin receiving and holding member such as a funnel F located at the top of table T and projecting upwardly therefrom, FlGURES l, 2, 5 and 6, into which pins are delivered at the proper time from the distributor cups, and within which they are supported in substantially centered rest position upon movable supports, such as trap doors 452. A pair or set of trap doors d5?. is mounted above each of the respotting cells R directly beneath the lower portion of each funnel F as indicated in FGURE 6. At the proper time in the cycle of operations of the machine, each of the ten sets of doors 52 is opened simultaneously and moved downwardly away from the pin which has been supported in each spotting device 451 so that all pins contained in the several spotting devices 451 are released substantially simultaneously and delivered to their desired spotted positions on the alley. Each set of doors 452 in addition to performing the function of supporting pins in spotting devices fidi for placement on the alley, is also designed to guide each pin into proper spotted position on the alley.

Mounted in the lower portion of table T within each cell R is a pair of opposed gripping bars or devices 45d, FGURES 4 and 6, which bars or devices are located beneath and in symmetrical arrangement with respect to eaoh set of doors 452. Bars may be formed of wood, metal or plastic or combinations thereof. gripping bars asas or devices 45d are movable toward and from each other for gripping and holding pins to be lifted from the alley during the removal of deadwood and unwanted pins and for respotting and releasing the pins held thereby in the respotted on or off-spot positions each pin occupied ready for the rolling of the next ball of the same frame. Each gripping bar or device ld preferably is provided with a covering, generally a resilient material, such as rublber, which insures a firm grip and also tends to prevent damage to the neel; portions of pins being gripped, lifted and respotted.

Referring to FIGURES 2, 5 and 6, each of the funnels F disclosed is formed with an inverted generally truncated conical or flaring shape with a relatively larger open top portion 456, and a tubular lower portion 469 which can be formed integrally therewith or attached thereto. Lower portion 46% preferably is cylindrical and therefore has a circular discharge bottom opening 453. The diameter of portion dat) preferably is only slightly greater than the maximum diameter of a bowling pin. The top portions 456 of tunnels F are flared laterally and are so positioned on table T with respect to distributor D that they register with the discharge openings of cups C thereon. The bottom openings 453 of funnels F, which are all positioned concentrically with the centers of the pin spots on a bowling alley, are disposed in a plane a short distance above the plane of the top faces of longitudinal members Lido.

As shown in FIGURES 5 and 6, the opposite sides of each member dat) are secured to the upper ends of oppositely directed supporting brackets 452. The lower ends 45t-t of brackets 462 are attached to the stationary parts 1h55 of hinges 457, which in turn are secured, as by bolts 47d, to the top `faces of frame members 4546. Stiffening mem-bers A73 and 476 are attached to brackets 472 secured to cylindrical portions dott of tunnels F.

Referring to FGURES 3, 5 and 6, each of the doors 452 consists essentially of a rectangular support, attached to or formed integrally with a hinge member o8 pivotally mounted on hinge pin du?. Doors 52 perform the dual function of supporting and guiding pins to be spotted, and also holding pins to be lifted and respotted in their respective on or off-spot positions so that such pins can be gripped properly for lifting and respotting. For this reason, the underside of each door preferably is provided with an undersurface which, when table T is lowered to respotting position, engages the head ends of any standing pins and holds them tirinly against lateral ymovement on the alley. A resilient material, such as sponge rubber pad 553, has been found to be satisfactory `for this purpose, see FlGURES 4, 6 and 1l.

The upper surface of each door 452 is provided with a pin guide 455. The guide can be formed integrally with door 452;, or as illustrated, can be attached to the upper surface thereof. ri`wenty guides are provided, one for each door, or two opposed guides for each set of doors 452. Since these guides are identical, only one is described in detail.

Each guide 45S is provided with an interior curved section A'-57 having an upwardly curved portion which generally conforms with the curve or taper of the butt end portion of a pin. Its shape is such that when doors i5-2. are closed and a pin to be spotted is resting thereon, the butt end of the pin is centered by the two opposed guides 4555 relative to the spotted position it will occupy on the alley. When doors 452 are opened, the butt end of the pin is guided continuously by opposed curved portions 457 of guides 455 as the pin passes downwardly therebetween onto the alley. The same operation occurs in each of the ten spotter units 45t.. Each guide is adjustably mount-ed on its respective supporting door 452, ln this manner, guide 45S of each unit 451 can be adjusted to and from or laterally relative to each other and secured by screws 459 passing through enlarged holes 463i in guides 455, FIGURE 3, in proper operative pin xsi-,erases supporting and guiding relationship for exact spotting on the alley.

.Each door 452 is actuated by a link lf/Hl, preferably having a ball joint end fitting $75, of any suitable con-` ventional type, which is pivotally connected to an upstanding flange E77 on hinge portion d68. For each pair of doors, two of the links 47d have their upper ends attached to a pivot block for synchronizing the action of the two doors with respect to each other. Each block @7S is mounted on a pivot 79 supported in the: free ends of two spaced crank arms i3d which are 'at-- tached to a rocker shaft @32. As seen in the drawings, the cell R, which corresponds to the position ofv vpin #1, may be considered typical of the ten cells R of table T. The movement of doors is effected by rotation of one of the shafts Referring to FGURE 2, rear shaft operates four sets of doors 4252; by virtue of having four sets of crank arms 45t) attached to it. To the right hand extremity of each of shafts i282 is xed a crank arm Since it is desirable to operate all of doors 452 simultaneously and to the same degree all of the rock shafts it-2 are similarly interconnected so as to be rotated to the same extent.

The first and fourth shaft 4?;2, as viewed from the bot tom of FiGURE 2, are each provided with a single crank arm ddd. These arms are of the same length and are iixed to the shafts to extend in the same angular relation thereto. The two crank arms Se on the driven rock shaft 482 (the third shaft as viewed from the bottom of FlGURE 2) are operatively connected respectively to the ends of the crank arms 48d on the two adjacent shafts 482 by links In turn, the second shaft from the bot-tom of FlGURl-E 2 is operatively connected to the fourth shaft 482 by a link 4iso pivotally attached to crank arms 434 on those shafts. Thus, upon oscillation of the driven rock shaft ad?. to a predetermined extent, all of the other shafts 432 will be turned to a similar extent and in the same direction to thereby rock the crank arms 430 on the shafts and simultaneously open all pairs of doors 452i through their respective blocks 473 and links 474%. Shafts 482 are journalled at their opposite ends in bearing brackets 49@ att-ached to the top faces of the side frame members 430.

ln FIGURES 2, 3, 5 and 6, the mechanism, including rock shafts 432 and links ddd and associated parts, is shown in a posi-tion in which the doors 452 are in closed position. That is to say, the mechanism thus far described constitutes synchronizing7 means for effecting like action on the doors in accordance with the actuation in the proper direction of the driven rock shaft 4552.

When the mechanism for operating shafts db2 is actuated, the driven rock shaft d2 is turned in a direction which results in releasing or free-ing, under mechanical control, the other rock shafts S2 so that they may be rotated in a direction to effect opening of the doors 452, under positive spring action. ln the drawings, FIGURES 2 and 3, there are shown such spring devices arranged on one en-d of the first and second of the shafts dill?. lt should be understood, however, that each of the four shafts 4tlg can also be provided with one of such devices on an end thereof. These devices are constructed and arranged to operate as follows:

A spring #592 of conventional torsion type has one end iixed to a bearing member 49@ in which an end of shaft 432 is journalled. The opposite end of spring 92 is attached to sleeve 49d loose on shaft 482. A smaller locking or clutch spring also surrounding shaft dei and having a close tolerance tit thereto has one of its ends attached to sleeve 494. By this combination of driving spring 492, attaching sleeve 49d and locking spring $96, it is possible to easily wind up spring E92 to any desired torque value, and the spring clutch locking action of spring 496 will then positively transmit that torque into shaft 482 to transmit motion for opening doors 452.

lt is desirable to regulate or control the closed position of the pairs of doors 452, in order to insure that the bottom faces of the pin head engaging surfaces 453 all lie in substantially the same horizontal plane to insure substantially uniform contact with the heads of standing pins. This result may be obtained by means of a series of lugs or members 5d@ attached to the transverse members i3d-ddd in position to extend inwardly a short distance over the edge of each cell. The bottom faces of f embers lie in the saine plane. Each member 56d prog? nts inwardly centrally of a cell so that portions of doors 452 of each pair, when moved to closed position, will abut against and be arrested in proper position by said extensions against further upward movement.

The main actuating rock shaft 432 in the illustrated embodiment is the third from the bottom, as viewed in FEGURE 2. Attached to one end of this shaft, which .actuates the three other shafts 482, is a crank arm 562, see FlGURE 8. The free end of arm Sill is connected to one end of an adjustable link 5nd, the other end of which link is connected by a pivot pin 51@ to one end of a link Silo. The other end of link 5% is pivotally attached to bracket 5tl9 mounted on the frame of table T, as shown in FlGURE 8, thus forming the elements of a typical four-bar linkage. A cam roller 512 mounted on pivot pin Slt) engages the cam faces of cams shown in FEGURE 9, to be described more fully hereinafter. The spring loading `of driven shaft 432, as previously described, tends to move the four-bar linkage in the general direction of arrow T shown in FTGURE 8.

Referring now -to FEGURE 9, when table T is in its full up position 492, roller 512 will be located at point iZA and yieldingly forced against cam face 14 by a suitable spring (not shown). As the table moves downwardly after the rolling of the first ball of a frame and when there are pins standing on the alley to be lifted and respotted, cam roller 512 `rolls from cam face 514 onto Ian upright cam face 516 to position 5MB. Cam face Slo is formed on a cam bar 517 pivoted at S18 on a plate 5119 xed to the machine frame. Table T in returning to its full up position, causes roller 512 to travel upwardly along cam face di@ and come to rest again at point SZA on cam face Sie. ln traversing this path, no hori- Zontal motion is transmitted to cam roller 5l2, hence no motion is transmitted through the four-bar linkage to the pairs of doors 6.552, and they .remain closed.

When a set of pins in spotter devices 451 is to be placed on the alley, table T moves downwardly and roller Sli moves from cam face Sid, downwardly along cam face Sie past pivot point Sid continuing downwardly and to the left along a sloping Cam face 52@ on bar S17 and thence to vertical cam face 522 on that bar. As roller lZ moves below pivot 5l- 8, bar 5l? swings clockwise on that pivot, as viewed in FGURE 2l, against the action of spring 526, until it bears against vertical cam face '524 on `a fixed bar 525.

Thus cam roller dll has moved in a horizontal direction a distance X (FIGURE 9), which motion is transmitted through the four-bar linkage previously described, thence through the door operatin-g mechanism. Doors 4.52 are opened a predetermined amount consistent with the movement X of roller SI12. in this position of roller ST2, doors 452 are almost completely opened, but not enough to allow the pin to drop through the door opening. As roller SEZ progresses downwardly to the end of cam face 5222, it rolls olf the lower end of bar 517 and abruptly engages against cam face 524 at position 512C. This last action of roller El?! in moving quickly from cam face 22 to cam face 52d, positively and quickly opens doors to their full extent and effects a quick release and deposit of a set of pins upon the alley. It is to be noted that each set of doors 452 opens sufficiently to clear a spotted pin entirely as table T moves upwardly.

Spring 525, as shown in FIGURE 9, urges pivoted cam bar 5l? in the direction indicated by arrow H. As

envases roller 512 passes downwardly along cam Afaces 52o and 522., spring pressure, derived from springs 492 and 4% on shafts 482, is snticient to overcome the action of spring 526 and shift bar 5X7 as stated. Upon upward movement of table T after a set of pins has been spotted, since cam roller SEZ has moved out of contact with the lower end of cam bar 5l7, spring 26 returns the bar to its normal position, which is determined by the engagernent of the upper end of bar 517 with a fixed inclined bar 52.7, the lower end of which aligns with the upper end of cam bar 525.

During the movement of table T upwardly after hay` ing deposited a set of pins on the alley, roller 512 rolls upwardly between bars 517 and 525 and along cam face 524 to position 5212i). It can be seen that in this vertical travel of roller str2, no displacement of roller 512 in the horizontal direction takes place. With cam roller SLlZ at position SlZD, the bottom edges of the now open doors 452 have ascended to a position above the tops and clear of the pins standing on the alley. As the table continues upward roller 512 passes along inclined cam face 528 of bar 527 and in so doing, contacts the inner face of the upper arm of the pivoted bar 517 and moves that bar on its pivot clockwise, as viewed in FIGURE 9, to allow passage to roller 512 out between bars 517 and 527 and back to its original position at 512A, resting against outer cam face 514.

Movement of cam roller 5l?. vfrom position 512D to 512A, causes roller 5l2 to be displaced horizontally a distance Y, as indicated, thus transmitting motion through the lfour-bar linkage and the previously described door-operating mechanism, rewinding springs 492 to effeet closing of the doors 452 against their stops Silit. In FIGURE 9, the position SZA, 512B, and 512C represent the position of the roller S12 corresponding to positions of the center of shaft 34h as represented at 4452, 494, and elle on FIGURE l. The position of roller 512 when the center of shaft 349 is at a position as represented at doti, is directly below roller position 512A.

Pin Respotting M echmzism Each of the ten cells R is provided with means, operative at the proper time in the bowling cycle, for gripping and holding pins to be lifted and replaced in their on and/or off-spot positions pending rolling of the next ball of the same frame. This gripping means includes the opposed pairs of substantially parallel arms of bars 455i. Since each pair or set of bars 45d is identical in con-struction and operation, it is deemed Sullicient to describe but one in detail.

The opposed pairs of gripper bars 451i, as indicated in FlG. 5, extend longitudinally relative to a bowling alley, although if desired, they could extend transversely or at an angle to the longitudinal axis of the frame of table T. ln their full open or inoperative positions, bars 45d are located adjacent opposite sides of cells R. One end of each gripper' har 456irs provided with a freely rotatable roller 531), FIGS. 5 and ll, located beneath a guide bar 533 attached to a channel section, as for example, 436. Roller 531) runs on a flange 531 formed on a transverse horizontal track bar 532 attached to a transverse member of a cell R.

ln the illustrated embodiment, see FIGURES 10 and 1l, actuation of each set of gripper arms 454 is effected by a self-centering, ve-bar linkage unit consisting of a pair of downwardly extending links 534, a pair of links 535 and a cross link 53S. The common pivot 539 between links 536 is attached to a slide Seit), slidably supported on and guided by a vertical track bar S42 attached to the upper flange of one or transverse beams 43o-fired by means of a clip The outer ends of links 536 are pivotally attached at 537 to the upper ends of links S34, which in turn are pivotally connected between tlteir ends to link 533.

Tension prings S46 are attached to the lower end of track bar 542 and to clips 54S on the pendant links 534. The purpose of springs 546 is to balance out the otherwise unbalanced forces occurring when the linkage mechanism is in one or another of its off-center positions. lt can be seen that an upward movement of slide Salti on trac-k bar 542 causes a displacement of the live-bar linkage described, such that gripper bars iS/i will be urged away from each other. This motion is comined vto a horizontal plane and straight line motion relative to the sides of a cell R by virtue of the roller and track arrangements 530, 532 and 533. Similarly a downward motion of slide 54d on track bar 542 causes gripper bars 454 to move toward each other. When the gripper arms 454 are urged away from each other, they come to rest symmetrically at opposite sides of a cell R. When gripper arms 454 are urged towards each other, the degree of freedom of movement allows each pair of gripper bars 454 to assume any position between the sides of its cell R depending upon the on or olhspot position of alpin gripped by the opposed bars 454. Each standing on and'oi-spot pin to be gripped, lifted and respotted, as described hereinafter, is clamped by the under surface of table trap doors 452 against alley A. Thus, when a normal on-spot clamped pin is to be gripped by bars 454 for lifting and respotting, each bar 454 moves substantially the same distance from its inoperative position adjacent the side of a cell R into gripping engage ment with a side of the neck of -a pin. Gripping bars are so located that when table T is positioned at position 404, bars 454 can engage and grip the necks of any standing pins to be lifted.

if a pin to be lifted and respotted occupies an ospot position, as soon as the bar 454 nearest the pin er1- gages it, the movement of the bar is arrested. The other gripper bar 454 of the pair, however, continues its forward movement into gripping engagement with the opposite side of the neck of the pin, whereupon its motion is arrested and the pin is iirmly gripped for lifting. The same operation takes place simultaneously with each of the ten pairs of gripper bars 454. it will be seen, therefore, that because of its operating connections, each bar 45d is given an on-spot, olf-spot range which allows each pair of bars to grip a pin anywhere Within the general area of a cell R. The pro-vision of elongated gripper bars or rollers 454 makes possible the positive gripping of onand off-spot pins: over substantially the entire area occupied by bowling pins on the pin supporting deck of an alley, which is a greater' area than heretofore available for this purpose. Parallelism of gripper bars 554 is maintained by the inherent tor sional rigidity of pendant links 53d. coupled with the resistance to bending and torsional stiffness of the rest of the five-bar linkage, and its associated parts and attachments, which make possible the individual and differential travel of each bar 454 of a pair of gripper bars 45dtowards an on or ott-spot pin.

T able Movftg Mechanism The ventical movement of table T is effected by the rotation of crank arms 33t) and the action of connecting rods 346, which in yturn imparts vertical reciprocating motion to the table T through connecting crank arms 344. n the travel of the table from full up position i632 to full down position 406, and return, crank arms 344 rat these positions remain substantially vertical, see PEGURE l, When, however, table T is stopped at respotting position 404, crank arms 33t) will be substantially in the position shown in dotted lines in FlGURE 7, and connecting rods 345 will be angularly displaced in approximately the manner shown in that ligure.

Arms 344 are freely journalled upon shaft 346 but are restrained from moving in a clockwise direction by adjustable stops 559 mounted in suitable ribs 551 on brackets 342 `and acting in conjunction with their respective 'stop pins 5543 integrally attached to and projecting from arm 344, see FEGURE 7. Further clockwise motion of crank arm 339, through the action of connecting rod 3415,

ill cause arm 34d to rotate in a counter-clockwise direction to a predetermined angle with respect to the table during the time the table is held at respot height or position ddd.

A crank arm 556 is 'fixed to each end of shaft and each carries an adjustable set screw S58. Each stop pin 55d is extended through an arm 34d to form at the opposite side thereof a drive pin 56d. When crank arms 35rd move in a counter-clockwise direction, each arm 344 rotates :freely on shaft 3d@ until drive pins Se@ thereon abut adjustable set screws 558. Further counter-clockwise motion of crank arms 3M will now impart counterclockwise rotary motion to shaft 340 through the desired angle, as previously mentioned. Shaft 34), See FlG- URES l and 2, comprises the rear shaft of a set of four shafts, the other three being designated 562, 564, and 566, respectively. These shafts are so arranged that when shaft 34d is rotated, shafts 562, S64 and 565 also rotate in the same direction and to an equal extent. rl'he operation of these shafts is used to actuate the gripper mechanisms simultaneously in all of the cells R. For example, shaft 340 when rotated, effects the simultaneous operation of the pairs of opposed gripper arms 454 in the four transversely arranged cells R at the rear of Ithe table, see FIGURE 2; shaft 562 effects like operation of the grippers 454 in the three cells forward of the four just mentioned; shaft 564 ope-rates the grippers 454 in the next two forward cells and shaft 566 effects a similar actuation of gripper 45d in the one cell at the front.

The four shafts preferably are interconnected for simultaneous rotation by means generally of the same sort as shown and described for the purpose of operating the door mechanism. For example, shaft 34d is provided with a crank 568 to which is pivoted one end of link 79 operatively connected at its other end to a similar crank S72. secured to shaft 562. This shaft has another crank 57d operatively connected by a link 576 to crank 573 on shaft 56d. Shaft S64, in turn, has a crank 5% operatively connected yto a crank 5&2 on shaft 566 by a link 58d.

Gripper Operating Mechanism Since the operation of the gripper mechanism in each cell R is identical, the descrip-tion will be limited to the operation of the gripper bars iSd in cell R corresponding to No. 1 pin position, see FlGURES 5, l() and ll.

A crank arm 5% is freely journalled on shaft 5&6 near its center. A collar 592 is secured to shaft 66 adjacent crank arm 5%. A pin 5523, FEGURE 1G, fixed to collar 592 engages slot 5%- in crank arm 5%. A torque spring 5% surrounding shaft Sodi has one end attached to crank arm 5% and its opposite end to an adjustable sleeve 5% encircling shafts 566. Also attached to sleeve 593 is one end of locking spring all@ which frictionally engages 'shaft 566 to positively position and lock spring 596 with respect to shaft 56d. The spring force exerted by spring 5% is such as to urge the outer end of crank arm 5% in a downward direction with respect to shaft [566, but such movement is normally prevented by pin 5% engaging the end of slot 52Mias indicated in FGURE 5. The outer end of crank arm S9@ is pivotally attached at til to one end of a connecting link 692. The other end of connecting link olli'. is attached by a cross-pin to pivot 539 between slide Sd@ and links lt can be seen that a counter-clockwise motion of crank arm 59d will, through connecting link 662, cause a downward movement of slide 54d. Conversely, a clockwise motion of crank arm 59d will cause an upward movement of slide 546. This clockwise motion is necessary for the operation of the five-bar linkage which in turn actuates gripper arms 45d in the manner described.

As slide Sdi? is moved downwardly, gripper bars 45d engage and grip the neck; and their farther inward movel2 ment is arrested. However, pin 593 at.ached to collar 592 on shaft E66, may, however, continue its counterclockwise motion within the space provided by slot rihis allows, in a cell where no pin is present, continued counter-clockwise motion of crank arm 590, pin 593, and the accompanying shaft as contrasted to an arrested or shorter stroke motion of crank arm 59?, as just described.

A tab 61M, FlGURES 3 and 5, carrying an adjustable set screw dilo is fixed to each crank arm 59d. A switch bracket 6%, FIGURE 5, supports a switch SW and actuator ed@ in the path of travel of set screw ln the event that the gripper bars 45d corne into engagement with a pin in their travel toward each other, they will be arrested short of con-tact with each other. ln this case, the movement of tab 6M carrying set screw nfld, and its supporting crank arm Stift, is arrested prior to contact of screw 6% with the switch actuator 669. if, however, there is no standing pin to be gripped or engaged by a pair of gripper arms 454, the latter will continue to move towards and into engagement with each other, in which case the crank arm 59d will cause the set screw 6% to move a greater distance and it will then come into contact with and operate the switch actuator dit@ for the corresponding switch SW1. A similar pin detecting device is provided for each pair of gripper arms 45d. It can be seen that the absence or presence of pins in cells R is electrically detected for cyclic control of the rnachine.

As previously described, it is possible for a pin to be so far off its normal on-spot position that the head of the pin will be engaged by one of the lower flanges or some part of .the lower section of the table frame structure. In' such an event the table will be stopped at a safety position designated 408, see FlGURE l.

The desired safety action may be effected by the engagement of a .set screw 622 on arm 621 arranged alongside tab 694, FIGURE 3, which screw will engage a switch actuator di@ to close its associated switch SW13, FIG- URE 5. Switch SWB may be arranged in the power supply line to open the line and stop the machine.

Switch SW1?) and switch SW3 are two switches operated by separate actuators (see FIG. 3). The switch SW1 actuator is adjusted such that it operates the switch when the grippers close beyond the point denoting a pin, when the table has descended to its full down position in the respot cycle. At this point, shaft S66 has not rotated sufficiently to actuate switch SWlS. This position is as far as shaft 566 rotates when the table is at normal down height. If, however, a pin is beyond normal respot range, the table will stop at a higher position due to the pin supporting the table by members 436, 433, ddt), 442, 444, and entre of FIG. 4; and shaft 66 will rotate further than necessary for normal pin gripping action. Switch actuator set screw 622 on arrn 621i. is so adjusted that with this amount of rotation of shaft 566, a larger rotation than is required to actuate switch SWL switch SWIS will be actuated. ln a strike cycle, switch SWB .is not actuated. Since no pins are left standing, the table descends its full amount (no off-spot pins hold it up) and shaft 566 does not rotate sufhciently yto actuate switch SWfr. Switch SW is actuated, however, if switch SWJLS is actuated, but switch SWS is not necessarily actuated if switch SW. is actuated inasmuch as a greater rotation of shaft "566 is required to actuate switch SVR/13 than is required to actuate switch SWL The switch SWll actuator set screw supporting arm 621 is attached to collar S92 which rotates with the shaft, whereas the switch SW1. actuator is attached to crank 5% which is rotated by the force of spring 5% whenever the shaft 566 rotates. Hence, the rotations of crank 59) and shaft are not necessarily the same. Shaft 556 can rotate a larger number of degrees than can crank 590 which stops rotation when the gripper arms come to rest either together or gripping a pin.

This higher than normal stopping position for the table 13 causes crank arm 344 .to be rotated in a counter-clockwise direction further than needed for operation of the pin gripping mechanism. The differential action just described between crank arm 590 and shaft 566 allows a sufficient degree of freedom to accommodate this execs sive angular motion of crank arm 344 and associated torque shafts 340, 562, 564 and 566 without mechanical damage to the spotting table and its associated mechamsm.

From the preceding descriptio-n, it may be seen that the electrical indication will be that no pins have remained standing and the cycle and scoring of the machine will be modified accordingly. This modification seldom takes place because of the infrcquency or" such an extreme offspot pin. It is considered in the design to prevent darnage to the machine.

The tendency of the gripper arms 454 lto close through the mechanism described is opposed by the force of a pair of springs 612, FIGURES l and 4. Thus when the holding or driving `force of connecting rod 346 is relaxed from crank arm 344, springs 612 will return bars 454 of the gripper mechanism to their full open or inoperative position. This, of course, releases any pins which are to be respotted on the alley. Springs 612 each have one end connected to` crank arms 579 extending from shaft 564. The opposite ends of springs 62 are attached to spring clips 614 on the lower `liange of transverse frame member 449.

Brackets 581L are secured to opposite sides of table frame 439. Adjustably mounted in brackets 583 are sto-p screws 581 adapted to be engaged by levers 579 on shaft 564. In this manner tbe opening movement of gripper bars 454 is restricted. This arrangement also prevents gripper bars 454 from striking against the end frames of their respective cells R if for any reason, table T should be released accidentally and drop suddenly to its lowermost position.

Attached to crank arm 568, see FIGURE 7, is a cam plate 615 which rotates with shaft 34d. A latch 616 pivoted at 617 on bracket 342 has one end arranged to engage a tooth on cam 6315 through the action of a spring 61S. This spring extends about armature 629 of solenoid 67.9 to which one end f latch lever 616 is pivoted. In the latched position, shaft 340 will have been rotated to the proper position for the gripper mechanism to have fully closed. When it is desired to lift pins from the alley, this cam and latch lock the gripper mechanism in its closed position. When the pins are again lowered to the alley, solenoid 620 is energized, thus releasing latch di from engagement with cam 615 and allowing springs 612 to return the several gripper arms 454 to their full open position. Similarly when it is desired, in the cycle of the machine, Ato electrically indicate the presence or absence of pins in the various cells R, solenoid 62d is energized while this standing pin detection is carried out, again allowing the gripper mechanism to return to its open position through the action of springs 612.

The invention above described may be varied in conruction within the scope of the claims, for the particular device, selected to illustrate our invention, is but one of the many possible concrete embodiments of the same. It is not, therefore, to be restricted to the precise details of the structure shown and described.

What is claimed is:

l. A spotting unit for a bowling pin spotting machine comprising a bowling pin guiding and positioning member, said member having an upper outwardly flared portion and a lower substantially cylindrical portion, means mounting said member with its longitudinal axis substantially vertical, a pair of opposed pin supporting and clamping trap doors, a pin positioning and guiding device on the upper surface of each of said trap doors for positioning pins on said trap doors and guiding movement of the pins as they are being discharged upon movement of said trap doors, a hinge supporting each of said trap doors beneath said lower portion of said member, means normally maintaining said trap doors positioned in a plane substantially at right angles with the longitudinal axis of said member for supporting the base of an upright bowling pin located within said lower portion of said member and between said positioning and guiding devices, said bowling pin guiding and positioning member being adapted to receive a bowling pin and guide such pin over said flared portion into said cylindriacl portion an dsaid pin positioning and guiding devices and onto said trap doors, and mechanism for moving said trap doors downwardly relative to a pin supported thereon, said mechanism including operating means for interrupting the movement of and locating said trap -doors in downwardly inclined partially open position with a pin supported by said trap doors between said positioning and guiding devices, and means for subsequently moving said trap doors and devices clear of said pin whereby said pin moves downwardly to complete the discharge of said pin from said unit.

2. In a bowling pin spotting machine, a device for placing bowling pins on the playing bed of an alley, said device having a plurality of pin spotting units arranged in substantially pin playing lformation, a driving shaft, an operating lever attached to said shaft, a shaft carried by said device, an arm loose on `said shaft, a link connecting said arm and said lever, interconnected operating mechanism for said pinspotters including an actuating shaft, a lever fixed to said actuating shaft, a link tired to said lever, a second link pivot-ally mounted on said device, va common pivot pin connecting the free ends of said links, a cam follower carried by said pivot pin, a cam tracked by said follower, means for driving said first-named shaft after each ball of a frame is thrown to lower and raise said device relative to said alley, and means selectively actuated by the presence or absence of a standing pin on said alley for causing said follower to travel alo-ng predetermined portions only of said earn for selectively operating said units.

3. In a pin spotter device, a frame, a plurality of pin spotting units mounted on said frame in an arrangement conforming with the playing arrangement of bowling pins on the playing bed of an alley, movable pin supporting and guiding plates forming a part of each of said units, actuating shafts for said plates, including a primary actuating shaft, interconnected operating elements connecting said shafts for substantially simultaneous operation of all of said plates, a lever fixed to said primary shaft, an operating linkage connected to said lever, including a cam follower, a pin spotter unit plate operating cam, said cam comprising a pivoted substantially vertical elongated section having an intermediate angular portion, and a second elongated substantially vertical section having an angular portion at its top end spaced therefrom and substantially parallel thereto, means for raising and lowering said frame, and selective mechanism operative in accordance with the travel of said cam follower on selected sections of said cam as the result of the movement of said frame for controlling the operation of said primary shaft.

4. In a bowling pin spotting machine, the combination of: a table mounted for vertical movement relative to a bowling alley between a plurality of positions including a spotting position, said table dening a plurality of triangularly arranged, vertically extended cells; means for moving said table; a plurality of pin guiding and positioning members mounted on said table above said cells, each of said members being adapted `to receive a bowling pin and position such pin so that its aXis is in alignment with one o-f Said cells; a plurality of sets of support plates pivotally mounted on said table, each set comprising a pair of plates mounted beneath a different one of said members and above the cell associated therewith, said pair of plates being movable between a closed position and a plurality of open positions, said plates when in said closed position supporting a pin in said member and movement of said plates from said ciosed position through said open positions being operative lto lower the pin supported thereby through the cell associated therewith; means for moving said plates between positions; and a pin positioning and guide device mounted on the upper surface or" each of said plates; each of said devices having a curved portion for guiding a pin so that its axis remains vertical as it is being lowered through said cell associated therewith toward a spotted position on the alley.

5. in a bowling pin spotting machine of the type having a frame supporting on its lower portion a plurality of pin gripping units, the combination of: means mounting said frame for movement relative to a bowling alley between a plurality of positions including a spotting position; means for moving said frame; a plural-ity of substantially cylindrical members each mounted on the upper portion of said frame for receiving and positioning a bowling pin so that the axis of such pin is substantially vertical; a plurality of sets of support plates each pivotally mounted on the upper portion of said frame beneath a different one of said members for movement between a tiret position and a second position, each set being arranged to support a bowling pin within said member associated therewith when said plates are in said irst position and to allow such pin to gravitate toward the alley upon movement of said plates from said first position toward said second position; a plurality of pin positioning and guide devices each mounted on the upper surface of a different one of said plates, each device having a first curved portion for.' positioning a pin and a second curved portion for guiding movement of a pin as it gravitates toward the alley so that the aXis of such pin remains vertical; and means for moving said plates from said iirst position to said second position to spot pins on the alley when said frame is in said spotting position.

6. In a bowling pin spotting machine, the combination of: a stationary support; a table mounted on said support for movement between a plurality of positions including a spotting position; means for moving said table; a plurality of spotting units carried by said table for spotting pins on said alley when said table is in said spotting position, each of said spotting units comprising a funnel adapted to receive a pin, a pair of trap doors pivotally mounted beneath said funnel and a pair of pin positioning and guide devices each mounted on a diierent one of said doors, said doors being movable between a closed position and a plurality of open positions, said doors being operative to support a bowling pin within said funnel when in said closed position and to discharge such pin from said funnel upon movement from said closed position through said open positions, said pin positioning and guide devices each including an arcuate portieri for positioning a pin on said trap doors and a curved portion which conforms generally with the taper of the butt-end of such pin for continuously guiding movement of and supporting such pin as it is being discharged so that the axis of such pin remains vertical; and means for moving said trap doors in response to movement of said table.

7. A bowling pin in accordance with claim 6 wherein said means for moving said trap doors comprises a cam mounted on said support and a cam follower carried by said table, said cam follower being operatively connected for actuating said trap doors, and said cam being arranged to actuate said cam follower, whereby pins are spotted on said alley as said table moves into said spot` ting position.

References Cited in the tile of this patent UNITED STATES PATENTS 

2. IN A BOWLING PIN SPOTTING MACHINE, A DEVICE FOR PLACING BOWLING PINS ON THE PLAYING BED OF AN ALLEY, SAID DEVICE HAVING A PLURALITY OF PIN SPOTTING UNITS ARRANGED IN SUBSTANTIALLY PIN PLAYING FORMATION, A DRIVING SHAFT, AN OPERATING LEVER ATTACHED TO SAID SHAFT, A SHAFT CARRIED BY SAID DEVICE, AN ARM LOOSE ON SAID SHAFT, A LINK CONNECTING SAID ARM AND SAID LEVER, INTERCONNECTED OPERATING MECHANISM FOR SAID PINSPOTTERS INCLUDING AN ACTUATING SHAFT, A LEVER FIXED TO SAID ACTUATING SHAFT, A LINK FIXED TO SAID LEVER, A SECOND LINK PIVOTALLY MOUNTED ON SAID DEVICE, A COMMON PIVOT PIN CONNECTING THE FREE ENDS OF SAID LINKS, A CAM FOLLOWER CARRIED BY SAID PIVOT PIN, A CAM TRACKED BY SAID FOLLOWER, MEANS FOR DRIVING SAID FIRST-NAMED SHAFT AFTER EACH BALL OF A FRAME IS THROWN TO LOWER AND RAISE SAID DEVICE RELATIVE TO SAID ALLEY, AND MEANS SELECTIVELY ACTUATED BY THE PRESENCE OR ABSENCE OF A STANDING PIN ON SAID ALLEY FOR CAUSING SAID FOLLOWER TO TRAVEL ALONG PREDETERMINED PORTIONS ONLY OF SAID CAM FOR SELECTIVELY OPERATING SAID UNITS. 